Directory creation and concurrency

Question

When requiring to create a folder in an action API, would there be any concurrency issue involved? If so, would the proper solution be to use a lock as in the following code

public async Task<IActionResult> UploadFile(User user){
     ...
     var file = HttpContext.Request.Form.File["SomeFile"];
     ...
     var path = Path.Combile(hostingEnvironment.WebRoot, configurationRoot["BaseDirectory"], user.Id);
     lock(path){
         if(!Directory.Exists(path)){
             Directory.CreateDirectory (path);
         }
     }
     ...
}

Would it be also logical to use the path variable as the lock object?

https://stackoverflow.com/questions/12804879/is-it-ok-to-use-a-string-as-a-lock-object — spender, Jun 11 '17 at 23:47
Why are you trying to lock at all? `CreateDirectory` won't throw if the directory exists — Panagiotis Kanavos, Jun 12 '17 at 07:13

mjwills · Accepted Answer · 2017-06-12T00:02:34.553

5

Just call Directory.CreateDirectory and don't stress about concurrency.

From the docs ( https://msdn.microsoft.com/en-us/library/54a0at6s(v=vs.110).aspx ) :

If the directory already exists, this method does not create a new directory, but it returns a DirectoryInfo object for the existing directory.

edited Jun 12 '17 at 00:02

answered Jun 11 '17 at 23:48

mjwills

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Isn't that `Directory.CreateDirectory`? – spender Jun 11 '17 at 23:50
It's also `CreateDirectory`, sorry I made the actual mistake! :D – Arnold Zahrneinder Jun 12 '17 at 00:01

Directory creation and concurrency

1 Answers1